Method of and machine for preblooming ingots



Feb. 15, 1944; 's E. DIESCHER 4 7 I METHOD OF AND MACHINE FORPREBLOOMING INGOTS I I Filed July 12, 1940 5 Sheets-Sheet 1 wmlassss. NINYENTOR.

- M (5 M/LM '44. ATTORNEYS.

Feb. 15, 1944:. 5', sc 2,341,910

METHOD OF AND MACHINE FOR PREBLOOMING INGOTS Filed July 12, 1940 5Sheets-Sheet 2 WITNESSES. J I ITOR. WW. I BY am flaw, fib M 4.,ATTORNEYS.

Feb. 15, 1944. DIESCHER 2,341,910

' METHOD OF AND MACHINE FOR PREBLOOMING INGOTS Filed July 12, 1940 5Sheets-Sheet 3 WITNESSES. v INVENTOR.

flak/Mm. BY M i 7 (Wm, I

44; ATTORNEYS.

Feb. 15, 1944. s. E. DIESCHER METHOD OF AND MACHINE FOR PREBLOOMINGINGOTS Filed Jur 12, 1940 5 Sheets-Sheet 4 WITNEJJEG.

15, 1944-, I s. E. DIESCHER 2,341,910

METHOD OF AND MACHINE FOR PREBLOOMINGINGOTS Filed July 12, 1940 5Sheets-Sheet 5 WT P INVENTOR.

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BY Q) 60 'LO'WW o'vrr M Patented at. 15, 1944 UNITED STATES Search RoomPATENT OFFICE METHOD OF AND MACHINE FOR PREBLOOMING INGOTS Samuel E.Diesclier, Pittsburgh, Pa.

Application July 12, 1940, Serial No. 345,154

16 Claims.

This invention has to do with treating steel ingots before they arereduced on blooming mills, the apparatus used for this treatment beingreferred to herein as a pre-bloomer.

Such ingots as are bloomed are always tapered longitudinally; that is,the cross section at one end is definitely less in area than at theother. The degrees of taper of ingots to be reduced in blooming millsvary over a considerable range, depending upon different mold designsand practices in teeming of the ingots. When ingots are reduced in ablooming mill the common practice is to subject them in their firstpasses to such an amount of reduction as quickly to convert their formsfrom pyramidal frusta to prismatic shapes, because otherwiseinconvenience in the manipulating of the ingots on the blooming milltables and accompanying delay in the procedure of blooming arise. Thelarge initial reductions that are thus brought about often createsurface cracks in the ingot of a character that can not be healed, andtherefore, in many instances, require to be chipped out or otherwiseremoved at later stages in the processing of the steel, the performanceof which conditioning is very expensive. To avoid some of suchconditioning, in some practices it is customary to baby the ingot in itsinitial passes through the blooming mill, by which is meant to operatethe mill slowly and with as small reductions as feasible. The delays indoing this not only add substantially to the cost of manufacture, butalso often create at the blooming stage of the series of proceduresinvolved in steel manufacturing a bottleneck that effects adversely theoutput of combined procedures.

The surfaces of ingots are inherently weak and are very likely toacquire cracks under any but the most cautious initial procedures, butif cautiously worked these surfaces become stronger and therefore moreresistant to the effects of rolling in the blooming mill. Thus it seemsclear that prior to any blooming mill deformation, which because of thegreat amount of displacement involved must necessarily be drastic, othermeans are badly needed for conditioning the ingot prior to blooming, theproviding of which means is the purpose of this invention.

The foregoing considerations apply to all forms of tapered ingots,whether they be round, square or slab shape in transverse section.Because it is becoming known that many steel from steel cast into round,as compared to rectangular cross-section, ingots, the use of such roundingots is now being strongly advocated. Like ingots of other shapes,they also are tapered from end to end. In reducing round ingots in ablooming mill it is necessary in the initial passes, in addition toremoving their tapers, to change them to forms that are substantiallysquare or rectangular in cross section.

The difficulties involved in the manipulation of round ingots to effectproperly their initial blooming passes are such that much more time isrequired to bloom them than to bloom rectangular or square ingots.

The object of this inventtion is to provide a method of and apparatusfor so treating or preblooming tapered ingots of any cross-sectionalshape that their surfaces will not suffer the impairments which attendsuch ingots when given the customary initial passes through a bloomingmill, that they may be bloomed more rapidly, and that round ingots maybe bloomed as rapidly as are those which are square or rectangularin'cross section.

The invention is illustrated in, and may best be explained withreference to, the accompanying drawings, of which Fig. 1 is a plan view,partly in section, of a machine for pro-blooming tapered ingots, in theoperation of which the method herein disclosed may be practiced;

0 similar to Fig. 6 showing rolls formed to act upon a rectangular ingotwhich is elongate in cross section; Fig. 8 a view corresponding to Fig.5 showing rolls acting upon an ingot that is generally circular in crosssection; and Fig. 9 a

diagrammatic view illustrating successive stages in the pre-blooming ofan ingot according to this invention.

In the practice of my invention a solid tapered steel ingot isrepeatedly moved, preferably with its small end foremost, through aclosed roll pass which is preferably formed by two pairs of oppositelydisposed rolls, one of which pair is slightly in advance of the other sothat the outer ends of one pair of roll faces products have bettercharacteristics if made will overlap the outer ends of the other pair ofroll faces in such a manner that a fully closed pass within all fourfaces is presented. Assuming the ingot to be substantially square incross section, in the first pass through the rolls the taper of aportion of the larger end of the ingot is removed by the reduction ofsuch portion to the contour of the pass. The ingot is then similarlymoved through the roll pass to remove its taper from an adjoiningsection and to further reduce the portion of the ingot previously movedthrough the pass. This operation is repeated to reduce progressivelylonger lengths of the ingot until its taper is removed and it is ofsubstantially uniform cross section from end to end. Preferably, themovements of the ingot are produced by pushing it upwardly through theroll pass to effect its successive reductions, and by lowering itbetween the rolls between successive reducing and taper-removingoperations.

The same procedure is followed when a round tapered ingot is thustreated or pre-bloomed to simultaneously remove its taper and convert itinto a form which is sufficiently rectangular in cross section to permitready manipulation on the blooming mill tables. However, for thaccomplishment of this dual result a greater number of passes may berequired than for preblooming rectangular ingots.

The number of pre-blooming passes given an ingot depends in part on itsoriginal taper, it being understood that to avoid the forming of surfacecracks and the enlargement of those originally existing it is desirableto effect a relatively small reduction in each of the passes. of thi itis desirable to give ingots having large tapers more passes than thosehaving small tapers. When an ingot is thus pre-bloomed it is renderedsubstantially uniform in cross section from end to end and may bereduced in a blooming mill without any delay in the initial passes andwith a far better surface.

This method of treating ingots will be further explained in connectionwith the following description of the pre-bloomer illustrated in thedrawings and by which the method may be practiced. Having referencefirst to Figs 1 and 2, a pre-blooming pass is formed between the opposedworking faces of two pairs of rolls I, 2 and 3, 4, each of which issupported by a housing 5. the construction of which will presently beexplained. As shown in Figs. 2 and 4, the movements of ingots upwardlythrough the pass formed by these rolls are preferably effected by a ramI mounted for vertical movement in a hydraulic cylinder 8 to whichpressure fluid may be fed and from which it may be discharged by aconduit 9 adapted to be connected to a source of pressure fluid supply.There may be several conduits 9, the number used depending upon theplunger speed desired. The upper end of the cylinder is encircled by andconnected to a supporting member H which is mounted upon a foundation l2and which is provided with a flange |3 that receives the lower ends ofguide rods M. The upper ends of these rods are anchored in the lugs ofbed plate IS, the latter forming'a cross as shown in Fig. l. The upperend of ram 7 is provided with a spider-like crosshead I! having bushedopenings in its projections for slidably receiving guide rods |4.Attached to the top of the ram is a tall pedestal la, the upper end ofwhich forms a base for supporting an ingot l9 as it is moved upwardlyand downwardly through the roll pass.

In view Each roll is in the form of a ring rotatably mounted on astationary shaft 2| carried by a vertically split housing 5 which isslidable toward and away from the roll pass in upright guide members 23at the opposite sides of the underlying bed plate IS. The housing isadjusted toward the roll pass by a pair of parallel screws 24 the frontends of which engage sockets 26 attached to the outer end of thehousing. Each screw is threaded through a nut 21 rigidly mounted in apedestal 28 supported by th bed plate, and has a smooth rear portionsplined in a worm gear 29 also carried by the pedestal. The two gear oneach pedestal are driven by a worm 3| from an electric motor 32supported at one side of the pedestal. Each stationary shaft 2| has oneach end a gudgeon for crane sling seating in changing rolls.

While the movement of each housing away from the center line of the rollpass may be effected by screws 24, such movement is preferablyaccomplished by a pair of rods 33 pivotally connected to the housingbelow the screws. The outer ends of these rods are pivotally connectedto a cross head 34 carried by the outer end of a plunger 36 slidablymounted in a fluid pressure cylinder 31 formed as a part of thepedestal. By moving the housing outwardly by fluid pressure in thecylinder as the screws are backed away from the pass, it becomesunnecessary to anchor the forward ends of the screws in the housin andthus eliminates a complicated connection. The pivotal connection of rods33 to the plunger and housing takes care of any vertical misalignmentdue to wear of the housing slides. The principal function of the fluidpressure arrangement is to eliminate clearance between screws 24 andtheir seats 26, thereby eliminating back lash, or pounding, when rolls 3and 4 and then rolls and 2 are brought into contact with the ingot.

In order to center each ingot on pedestal |8 before it is raised intothe roll pass the first time, the opposite sides of the ingot areengaged by centering members 4| spaced equal distance from the centerline of the pass toward which they are movable, as shown in Figs. 2 and3. Preferably, each centering member is moved horizontally by a pair ofrods 42 the outer ends'of which are connected to a block 43 that isslidably mounted between two stationary blocks 44 supported by theoverlying bed plate. Each of the stationary blocks is provided with afluid pressure cylinder 46, slidably mounted in which is a plunger 41that is attached to the slidable block 43. When fluid pressure isintroduced into one cylinder or the other, the slidable block moves rods42 and the attached centering member 4| toward or away from the centerline of the roll pass.

In pushing the lower end of the ingot up through the roll pass the baseof elevating pedestal 8 rises so high that it strikes centering members4|. To prevent these members 4| from interfering with further upwardmovement of pedestal base l8, each member 4| is connected at its outerend to adjoining rods 42 by a pivot pin 48 which projects from the rodsand into horizontal slots in a supporting member 49 suspended from thebottom of bed plate I6. Thus, when the rising pedestal base strikescentering members 4| it swings them upwardly out of the way. As pedestall8 recedes on the downward stroke of ram 1, the centering members 4|return, by gravity, to guiding position. This uidshims between the frameand housing.

in: position of members an is controlled by lugs 50 at these outer endswhich slidably bear against the bottoms of bed plates II.

To insure all of the centering members moving exactly in unison theirmovements may be controlled by controlling the pressure fluid suppliedto cylinders 46 so that the same amount is operation is repeated asoften as is-necessary by adjusting-the rolls successively tothe..p'ositions indicated by the arcs II and It. the successive suppliedto each. or, as is preferred, a gearing mechanism may be used that tiesthem together. Thus, the bottom of each slidable block I! is providedwith rack teeth which register with a gear pivotally mounted on a shaft52 below it; The various shafts are geared together by miter gears 53 attheir. ends so that they all must turn together, and thus maintain theguiding faces of though, asshown in Fig. 'l, the pre-bloonier is therespectiveopposite members ti equidistant from the center line of thepass.

To aid in guiding the ingot into the roll pass a pair of guide members58 (Fig. 2) ai'e disposed between the upp r pair or rolls i and 2 andcentering members 4 I. Preferably, each guide memher is attached to thebottom of the adjacent first to remove its taper and-then to bring itsufficiently to a rectangular form to aflord easy housing 22 near itsouter end and extends inwardly therefrom under roll I or 2 to the pass.

Any suitable means, such as an eccentric adjustment 51 (Fig. 3), can beused for adjusting the guide member toward and away from the passindependently of the roll above it. Such adjustments are forcompensating for roll wear and ingots of various tapers. Two pairs ofguides 58 are also mounted above the rolls to prevent the ingot fromtoppling over when in its uppermost position. These guides preferablyare pivoted on horizontal axes in frames 59 mounted on the rollhousings. The lower end of each guide slides on the underlying roll,and. the supporting frame is adjustable towardand away from theelongations of the ingot beingindicated by the lines u, u, u and a. Itwill be understood that r the other pairs of rolls, whichfor simplicityare not shown in Fig. 9. are adjusted similar to the rolls shown foreach pass.

- The foregoing explanatlon'of the procedure applies particularlytoingots which-are in cross section. The same procedure is "followedwhen rectangular ingots are .pre-bloo ned, al-

then equipped with rolls to and la wider faces than those ofrolls Iand}. In "removing the' taper from and reducing the cross section of aroundingot, additional passes'are manipulation in the blooming milloperation to follow. The-position of the'two pairs of rollsat thebeginning of the pre bI 'oming' of a circular ingot is shown in'Fig. 8.when an ingotolsny form is thus pro-bloomed, it may be either from theupper end of pedestal "onto a con,- veyor leading to a blooming mill,or,, if, desired. it may be returned to a soaking pit to give it .a washheat. v

By pre-blooming ingots according to this invention, the'delay incidentto .the babyingf ingot in a blooming mill is eliminated'andlieijlce ithe time for blooming each ingot is materially reduced. While this is asubstantial advantage. a more important advantage of m lnvention -re'sides. in the eliminationof the formationof surface cracks whichfrequently arise in thedniidrtl passes of an ingot through ablooming'r'nill,

roll pass independently or. the roll in any suitable manner, such as,for instance, by the use of M In the pre-blooming of an ingot by thisapparatus, ram 1 is first moved upwardly to position the upper'end ofpedestal ll above the portion of the pas formed by upper rolls l and 2,

all of the rolls being then in their spread-apart a position in' which aportion of the taper of the lower end of the ingot is removed by theupward movement of ram 1.

In Fig. 9 the positions of a pair of rolls relative to an ingot arevindicated diagrammatically for each of several passes of the ingotbetween the rolls. In the first pass the rolls are adjusted. as shown atthe lower end of the ingot.v to re- ,move the taper from the p rtion ofthe ingot,

below a' horizontal plane indicated by the line ll. In such operation,the reduction of. the ingot results in its becoming but slightlyelongated to an extent indicated by the dotted line ii. To avoidneedless chilling of the ingot surface, the rolls may be adjustedoutwardly, but regardless of this they are next adjusted towards thecenter line of the roll pass to the positions indicated by the arcs 63.When the ingot is again moved upwardly, its taper is removed between thehorizontal planes 60 and I4, and below the plane indicated at 60 theingofis further reduced. This The rolls ar then moved by also in theelimination of enlargements ofcrak's originally present on the surfacesof ingots. By

pushing the ingot through e closed pass in the manner of an extrudingoperation it is sary to make substantially large reductions in eachpass, as maybe done in a blooming rolls of which are frequently soadiustedas to grip the small end of an. ns0t umoie t1ytb posi;

tively' feed the ingot through he rolls. As a re-v sult of. making smalltaper ellminating and in got-reducing reductions, not only is thesurface of the metal not impaired. but the structure characteristics orthe metal are improved as comparedyith products dependent upon effectingmill. Y

It will be. understood that the passes through the pre bloomer areshorter in length than-those through the bloomingmill to whichprebloomed ingots are fed, and that for the successive passes of theprogressively elongated ingot through the blooming an increased amountof time is required. To increasethe rate of production of the bloomingmill, it may in some cases be advantageous to pre-bloom ingots to agreater extent than is required 'merelytoremov'e tap The amount of suchadditional reduction effected in the prg hlooni'e'rwilldepend upon thetime required to do it as compared with that required for the subsequentblooming. By way of example, if normal ire-blooming" l half as much timeas iln'al blooming. additional reductions may be made in. thepre-bloomer with the result that less time would be required in finalblooming. Thenet result of this will be to' increase the rate ofproduction of bloomed ingots.

The type of rolls described herein lend themselves to bflg made ofdiameters larger than the entire reduction in a blooming.

normally used in blooming mills. This provides flatter arcs of contactwith the ingot surfaces and thus tends not only better to compact thesurfaces thereof but also to offer less resistance against the ingotbeing forced through the pass. The concave working faces shown on therolls provide for easing the strain at the corners of the ingotcross-section and thus reduce any tende'ncy for cracks to form at thecorners. The rolls, being mounted on anti-friction hearings, will tendto drift after losing contact with the ingot. This exposes new surfacesof the rolls to the work, thus tending to avoid local heating and alsoto distribute wear and thus to lengthen roll life. Also shafts 2| mayoccasionally be shifted to new circumferential positions, thusdistributing irregular wear under localized pressures at anti-frictionbearings and at end supports, thereby adding to the life of thebearings.

Also it may in some cases be desired to prebloom ingots with their buttends up. 'This could readily be accomplished by the method described.

According to the provisions of the patent statutes, I have explained theprinciple and mode of operation of my invention and have illustrated anddescribed novel apparatus upon which it maybe practiced. However, Idesire to have it understood that, within the scope of the appendedclaims, the invention may be practiced otherwise than as specificallydescribed and with apparatus other than that herein illustrated.

I claim:

1. The method of treating a solid tapered steel ingot prior to bloomingit, comprising periodically moving the ingot small end foremost througha closed pass to roll it, and decreasing ,the area of the pass betweeneach rolling operation to reduce progressively longer lengths of du'eedin progressively longer lengths substantially to uniform cross sectionfrom end to end.

8. The method of treating a solid tapered steel ingot prior to bloomingit, comprising moving the ingot through a substantially rectangularclosed pass nearly as large as the large end of the ingot. and formed bytwo pairs of oppositely disposed rolls positioned one pair in advance ofthe other, periodically adjusting the rolls of .each pair thereoftowards the center line 'of their pass whereby 'todecrease the areathereof, and aftereach such adjustment of the pass moving the ingotthrough it to reduce progressively longer lengths of the ingot until itis of substantially uniform cross section from end.

ingot prior to blooming it, comprising pushing the'ingot with itssmaller end foremost through a closed pass and therebyreducing aportionof the larger end of the ingot, and repeating this operationthrough the same pass reduced in area; between each operation until theingot is reduced substantially to uniform cross section from end to end.

3. The method of treating a solid tapered steel ingot, in a closed rollpass comprising pushing the ingot upwardly with its smaller enduppermost through said pass to thereby reduce only the larger portion ofthe ingot, and repeating this operation through the same roll pass.reduced in area between each operation until the ingot is rolledthroughout its length and is reduced substantially to uniform crosssection from end to end.

4. The method of treating a solid tapered steel ingot prior to bloomingit, comprising periodically movingthe ingot through a closed passinivtially nearly as large as thelarge end of said ingot, and decreasingthe area of the pass between each rolling operation to reduceprogressively longer lengths of the ingot until it is of substantiallyuniform cross section from end to end.

5. The method of treating a solid tapered steel ingot prior to bloomingit, comprising pu'shing the ingot upwardly through a'closed passinitially nearly as large as the large end of said ingot, the smallerend of the ingot being uppermost, then lowering the ingot, reducingthesize v of saidpass, andrepeating said raising and lowering and passreduction until the ingot is re- 8. A machine for pre-blooming taperedingots, comprising two pairs of oppomtely disposed rolls positioned onepair in advance of the other to form a substantially rectangular passwhose center line extends vertically, means for adjusting' the rollstowards and from the center line of their pass, and means for repeatedlyelevating a taperedingot through the pass formed by the rolls to reduceprogressively longer lengths of the ingot until it is of substantiallyuniform cross section from end to end.

9. A machine for pre-.-b1ooming tapered ingots, comprising two pairs ofoppositely disposed rolls positioned one pair in advance of the other toform a substantially rectangular pass whose center line extendsvertically, means for adjusting the roll towards the center line of theroll pass, a pedestal for supporting a tapered ingot in upright positionin the line of pass, fluid pressure means for elevating said pedestal toforce a tapered ingot between the rolls whereby to removeits taper,guide members for guiding the ingot in its vertical travel, and meansfor retracting said rolls and guide members. suiilciently to permit saidpedestal and fluid pressure means to be lifted up between the rolls andthe ingot removed.

10. A machine for pre-blooming tapered ingots, comprising two pairs ofoppositely disposed rolls positioned one pair in advance of the other toform a substantially rectangular pass, screw means for adjustingv therolls towards the-center line of their pass, fluid pressure means forretracting said rolls, and means for repeatedly moving a tapered ingotthrough the pass formed by the rolls to reduce. progressively longerlengths of the ingot until it is of substantially uniform cross sectionfrom end to end.

11 A machine-for pre-blooming tapered ingots; comprising two pairs of'oppositely disposed 7 rolls positioned one pair in advance of the otherings and rolls inwardly towards the center line of the roll pass, afluid pressure cylinder spaced outwardly from each housing, a plungerslidably mounted in the outer end of each cylinder, a link pivotallyconnected toThe outer end of each plunger and the adjacent housingwhereby to retract the housing, and means for repeatedly moving atapered ingot through the pass formed gots, comprising two pairs ofoppositely disposed rolls positioned one pair in advance of the other toform a substantially rectangular pass whose center line extendsvertically, means for adjusting the rolls towards and from the centerline of their pass, means to! repeatedly elevating a ta ered ingotthrough the pass formed by the rollsv to reduce progressively longerlengths of the ingot until it is of substantially uniform cross sectionfrom end to end, means between said rolls and elevating means forguiding the ingot into the roll pass, said guiding means beingadjustable in unison with said rolls toward and away from the centerline of the pass, and means for adjusting said guiding means relativetothe pass to compensate for wear of the rolls.

13. A machine for ,pre-blooming tapered ingots, comprising two pairs ofoppositely disposed.

rolls positioned one pair in advance of the other to form asubstantially rectangular pass whose center line extends vertically,means for adjusting the rolls towards and from the center line of theirpass, means for repeatedly elevating a tapered ingot'through the passformed by the rolls to reduce progressively longer lengths of the ingotuntil it is of substantially uniform cross section from end to end, andmeans for centering an ingot on said elevating means prior to beingelevated.

' 14. A machine for pro-blooming tapered ingots, comprising-two pairs ofoppositely disposed mils positioned one pair in advance of the other toform a substantially rectangularpass whose center line extendsvertically, means for adjustgots, comprising two pairs 01" oppositelydisposed rolls positioned one pair in advance oi the other to form asubstantially rectangular pass whose center line extends vertically,means for adjusting the rolls towards and from the center line of theirpass, means for repeatedly elevating a tapered ingot through the passformed by the rolls to reduce progressively longer lengths of the ingotuntil it is of substantially uniform cross section from end to end, andlateralLv movable members for eng slns the sides of an ingot to centerit on said elevating means, the outer end of each of said members beingpivotally mounted on a horizontal axis whereby it is movable upwardlywhen struck by the rising elevating means.

l6. A machine for pre-blooming tapered ingots, comprising two pairs ofoppositely disposed rolls positioned one pair in advance of the other toform a substantially rectangular pass whose center-line extendsvertically, means for adjusting the rolls'towards and from the centerline of their pass, means for repeatedly elevating a tapered ingotthrough the pass formed by the rolls to reduce progressively longerlengths of the ingot until it is of substantially uniform cross sectionfrom end to end, laterally movable members for engaging the sides of aningot to center it on said elevating means, a ij'luid pressure motorspaced outwardly from each of said members and connected thereto foractuating said members, and all of said motors being geared tosether forcontrolled movement in unison.

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